Clamp for key cutter



' 1957 w. R. G. HAGGSTROM 3,301,549

CLAMP FOR KEY CUTTER Original Filed Aug. 25, 1961 BY Manx/ WW ATTORNEY 3,301,549 CLAMP FOR KEY CUTTER v Walter R. G.,Haggstrom,- Westminster, Mass.,-assignor to Independent Lock Company, Fitchburg, Mass., a corporation of Massachusetts Original application Aug. 25, 1961, Ser. No. 133,957.

Divided and this application Feb. 5, 1964, Ser. No. 347,331

' t 1 Claim. (Cl. 269153) This application is a division of my application Serial No. 133,957, filed August 25, 1961, entitled, Key Cutter.

This invention relates to a key duplicating device, and more particularly. to a clamp assembly therefor.

A feature of the invention is the provision of a key clamp mechanism whereby a key and key blank may be inserted into receptacles provided therefor, either manu ally or automatically, and whrch, when properly seated,

will be firmly. and fixedly clamped during the key cutting cycle of the deviceand released at the completion of such cycle. I i i A further feature ofthe invention lies in a novel key clamp which will fixedly clamp a blank and a patterned or cut key through the actuation of a single mechanism, notwithstanding possible thickness differentials existing between the key, and the blank.

Accordingly, it is an object of this invention to provide a key clamp for holding a key and key blank, the jaws of which are actuated by a single, shiftable actuator and which nonetheless may accommodate itself to simultaneouslyand accurately seating and holding a key and key blank of equal or disparate thickness.

To attain these objects and such further objects as may appear herein or be hereinafter pointed out, reference is made to the accompanying drawings, forming a part hereof, in which:

FIGURE 1 is a perspective view of portions of a key clamp mechanism in accordance with the invention;

FIGURE 2 is a vertical sectional view through a clamp mechanism of FIGURE 1.

In accordance with the invention, there is shown in FIGURE 1 a key duplicator clamp for holding a key and key blank during cutting which includes a vise block or jig 21 supported adjacent a forward part of the key cutting machine (not shown). Formed in the block 21 are a pair of key seats 23, 24 for holding the key blank KB and the pattern, bitted key K, respectively. The seats 23, 24 include bottom or floor portions 31, 32, respectively, and side guide wall portions 27, 28, respectively, perpendicular to the base or floor portions. The base portions 31, 32 are disposed in co-planar alignment to assure that the key and key blank, when properly positioned, will be at the same height. The guide wall 27 is parallel to the guide Wall 28.

The key blank and key, KB and K, respectively, are supported in the seats 23, 24 by laterally movable jaw members 71, 72, slidably mounted in a laterally extending channel 100.

To the end of the jaw 71 there is mounted a leaf spring 25 which extends at a rearward angle toward wall 27. A leaf spring 26 is similarly fixed to the jaw member 72 extending toward the wall 28. The leaf spring members 25, 26 bias the jaws away from the walls 27, 28, respectively, and toward the inner walls 29, 30, respectively, defining the seats 23, 24, respectively.

The vise block or jig 21 is provided with a vertically extending bearing aperture 77, Within which is rotatably mounted a shaft 76. The shaft 76, as seen in FIGURE 2, is provided with a range of lateral movement within the oversized bearing aperture 77.

An eccentric, generally oval cam member 75 is keyed to the shaft 76, the lobes of the cam or eccentric 75 being disposed against the inner ends 73,74 of the jaws 71, 72, respectively. Means are provided for rotating the shaft 76, thus to cause portions of the eccentric 75 progressively radially outwardly spaced from the axis of the shaft 76, to be contacted with the ends 73, 74 of the jaws 71, 72. Such means, in the illustrated embodiment of the invention, take the form of a lever 79 keyed to the shaft 76, the lever being actuatable by clockwise or counter-clockwise rotation to rotate the cam 75 and thus, in accordance with the direction of rotation, either press the jaws 71, 72 outwardly or release the jaws.

The leaf springs 25, 26 are attached to the jaws 71, 72 at a position adjacent the front wall 101 of the jig. The

" front wall portion 101 of the jig, adjacent the seats 23,

24, acts in the usual mannerv as a stop to limit inward insertion of the key blank and key, KB and K, respectively, by engagement with the usual extending shoulder portions formed on all key blanks and keys.

The device will normally be disposed in open position, as shown in FIGURE 1, by the outward force exerted by the leaf springs 25, 26 against guide walls 27, 28, respectively. Such force will tend to shift the jaw members 71, 72 inwardly, so that the ends 73, 74, respectively, ride against a relatively narrow peripheral portion of the cam 75. In this position, a key blank KB may be inserted into the space defined between the guide wall 27 and the inclined spring 25, the tip of the key being pressed rearwardly until the depending shoulder portion of the key blank rests against the front wall 101. The key blank KB will be retained in this position by the outward pressure exerted by the spring 25.

In a similar manner, the key K may be inserted into the space defined between the spring 26 and the guide wall 28 until the shoulder of the key engages against the portion of the front wall 101 adjacent the seat 24. The key K will similarly be maintained by the spring pressure exerted by the leaf spring 26.

When it is desired to lock the key blank and key in their respective seats 23, 24, the locking lever 79 is operated to rotate the cam 75 in the manner previously described, bringing wider portions of the eccentric cam 75 into contact with the ends 73, 74 of the jaws 71, 72, respectively. Such rotating action will tend to slide the jaws outwardly to the position shown in FIGURE 2 wherein springs 25, 26 are compressed tightly against the sides of the key blank and key, urging the opposite sides of said key blank and key against the guide walls 27, 28, respectively.

It is a feature of the device of the present invention that a tight clamping action against the sides of a key blank and key may be attained notwithstanding a differential thickness between the key blank and key.

In the illustration of FIGURE 2, the key blank KB has intentionally been illustrated as oversized in thickness as contrasted with the thickness of the key K. Both the key blank and key have been tightly clamped in position by rotation of the eccentric 75. This is due to the ability of shaft 76 to shift laterally within bearing 77 and, as shown in said FIGURE 2, the oversized key blank KB has caused the center of shaft 76 to move to the right, as

shown in FIGURE 2, to compensate for the disparate thicknesses of the key blank and key.

When the shaft is counter-rotated, the relatively thinner portion of the cam or eccentric 75 will be disposed adjacent the ends 73, 74 of the clamp jaws 7'1, 72, respectively, and the jaws will be caused to shift inwardly under the pressure of springs 25, 26, respectively. In this position, the key blank and key may be manually removed from the seats 23, 24.

It will be understood that in accordance with standard key cutting practice, the clamp mechanism will be used in conjunction with a key cutter and tracer assembly which is caused to move relative to the jig or clamp assembly in such manner that the tracer engages and follows the indentations of the key K, and the cutter, which is fixed against movement relative to the tracer, forms comparable indentations in the key blank KB.

-Optionally, in order to seat the base of the key blank and key against the bottom or floor portions 31, 32, hold down members 41, 42 may be provided, which hold down members, prior to cutting of the key blank, are pivoted clear of the key blank and key, to permit the tracer directly to contact the upper edge of the key, and the cutter directly to contact the upper edge of the key blank.

Having thus described the invention and illustrated its use, What is claimed as new and is desired to be secured by Letters Patent is:

A key duplicator clamp for holding a key and key blank during cutting, comprising a support jig having a front wall and first and second spaced parallel guide wall members, first and second jaw members slidably mounted on said jig and shift-able toward and away from said first and second guide wall members, respectively, eccentric means disposed between and engaging said first and second jaw members, bearing means on said jig rotatably supporting said eccentric means, said eccentric means and bearing means being laterally shiftable relative to each other in a plane normal to the plane of said walls, means for rotating said eccentric means, and leaf spring means interposed between said members for biasing said jaw members to a normal position spaced from said wall members, said leaf spring means being attached to one of said members adjacent said front wall and extending angularly rearwardly into contact with the other said member whereby said leaf spring means act temporarily to support a key inserted between said spring means and members prior to movement of said jaw members toward said wall members.

References Cited by the Examiner UNITED STATES PATENTS 10,508- 2/1854 Kneoht 269l53 1,821,163 9/1931 King 269153 2,349,291 5/1944 Meister 269-153 ROBERT C. RIORDON, Primary Examiner.

B. S. MOWRY, Assistant Examiner. 

